Create one HttpHandler, in that reference the dll and do all you need in ProcessRequest. From javascript, call the handler to fetch the response. If you want to use Javascript to access WebMethod, you can also do that using PageMethod, for which you need to expose the methods as Web Service. Take a look into this : http://forums.asp.net/p/1266663/2382644.aspx[^] :)
Abhishek Sur **Don't forget to click "Good Answer" if you like this Solution.
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